Project Summary/Abstract: This competing application seeks an additional five years (Years 6-10) of support for a post-doctoral research training program in pain and substance use disorders. The magnitude of these two problems in the US is astounding. More than 100 million Americans have pain that persists for weeks to years and over 20 million meet diagnostic criteria for an alcohol/drug use disorder. According to the National Academy of Medicine?s (NAM) report, Relieving Pain in America and the Surgeon General?s report Facing Addiction, these problems cost society almost $1 trillion annually. Contemporary neurobiologic, psychological, and epidemiologic research as well as the tragic experience of the opioid addiction epidemic show a clear intersection of pain and SUDs. Two of the NAM committee?s recommendations for improving research at a national level are (1) increase support for interdisciplinary research in pain, and (2) increase the training of pain researchers. Similarly, NIDA?s strategic goals and the Surgeon General?s report call for the multidisciplinary training of scientists to address the complexities of SUD research. In this proposal, we describe a collaborative, postdoctoral (PhD, MD/PhD and MD), interdisciplinary training program that will produce scientists with rigorous grounding in pain and SUD research. The accomplished faculty are all committed to interdisciplinary collaboration and mentorship across their substantive areas of expertise, which range from cells-to-society. The training program includes both required and elective coursework, mentored research experiences, an individual integrated research project, seminars, and exposure to professional development skills, including grant proposal and manuscript writing. The training program housed in the Division of Pain Medicine, Department of Anesthesiology, Stanford University School of Medicine, is intended to develop postdoctoral trainees? skills, so that they will become independent investigators in the fields of pain, SUD and their intersection. The training program will be led by Dr. Sean Mackey, in collaboration with a steering committee comprising senior scientist/mentors. They will oversee the training, scientific, and administrative aspects of the program, including a rigorous process of internal and external evaluation. In summary, this training program will bring together a talented group of post-doctoral trainees, an accomplished team of interdisciplinary mentors, an effective administrative structure, and a world- class research environment at Stanford University. The combination of talent and environment will launch the next generation of researchers who will advance our scientific knowledge and practice of pain and substance use disorders.